O'Connor Spreads the Word About Frankenskeeters

By Andrew McCullough - In the Florida Keys, long-running debates about how to combat mosquito-borne diseases show no sign of abating. On February 21, 2017, Anne O’Connor, PhD student in cultural studies, described the complex web of scientific, environmental, social, and political issues surrounding the use of genetic engineering to control native mosquito populations.

Since long before the 2015 Zika outbreak, researchers have been developing advanced methods to reduce mosquito populations. One such method involves releasing genetically-engineered or transgenic mosquitos (sometimes called “Frankenskeeters”) that inhibit reproduction. Deployed at a number of sites in Brazil, this technique has not yet been tested in the United States, where regulations are tighter.

Anne O’Connor conducted field research near Piracicaba, Brazil, where transgenic mosquitos have been released, and in Key West, Florida, where the debate over genetically-engineered mosquitos is ongoing. To understand the myriad issues brought to light by debates over the use of transgenic mosquitos, O’Connor spoke with parties on all sides: advocates and detractors, scientists, politicians, and local residents.

Simplicity vs. science

Detractors favor simpler, community-oriented approaches over advanced scientific ones. Mosquito-borne diseases are primarily spread by only a few species of mosquito (Aedes aegypti, for example), in part because they prefer to live in close proximity to humans. Since any means of reducing Aedes aegypti populations should be effective in combating disease, some locals prefer more straightforward methods, such as the removal of breeding grounds (ponds, lakes, etc.). However, because mosquitos require very little water to breed, even minor lapses in community practices can result in rapid population increases. Such issues lead to questions about individuals’ rights—for example, whether or not government officials should be permitted to inspect private property.

Scientific approaches range from older methods, such as draining swamp regions and spraying larvicide, to recent advancements like transgenic species. These methods can be more consistently effective than community practices. However, because the majority of mosquito species are not a threat to humans, approaches that broadly target many species are inefficient and may also have serious adverse effects. For example, draining swamplands or dispersing toxic chemicals is likely to impact many species besides Aedes aegypti.

Genetics research has led to a more targeted scientific approach. Researchers have developed species of mosquitos that have a “delayed mortality” gene. The transgenic insects can breed with native mosquitos, but will produce unviable offspring, thus reducing local mosquito populations. The approach is narrowly targeted to the disease-carrying species, and involves no toxins or major physical alteration of the environment.

Inherent uncertainty

Releasing transgenic mosquitoes in Key West would represent the first field trial in the United States. But the six-year debate over whether or not to do so continues unabated. One point of contention is the risk of inadvertently increasing populations while trying to reduce them. For example, since only female mosquitos bite, the researchers would attempt to release only males. However, there is a risk that a small percentage of females would be released.

Understanding the risks and predicting possible environmental effects is difficult. Even more challenging is communicating those risks to the public, particularly as many people fail to understand that uncertainty is inherent to science. Worse, scientists often fail to communicate risks in understandable ways, either in order to seem more unequivocal about the science or to simplify their message to the public. This can lead people to “do their own digging” on the internet, where they may find gaps in the science that weren’t communicated locally. In some cases, activists have used this doubt to foster broad mistrust in scientists and government officials.

Fear of the other

The debate intersects with politics as well, particularly when there is a scare of disease outbreak. During the recent Brazilian Zika outbreak, elected officials rushed to action. But many citizens felt the politicians were primarily motivated by the desire to appear to be taking action. In the US, politicians are also viewed by some activists as politicizing the issues of disease risks and transgenic mosquitos, rather than attempting to inform and help the public.

Issues of nationality, race, and immigration policy have also entered into the discourse. For example, some people seem to have an implicit attitude that the mosquitos transmit diseases brought to the US by other people. These “others” might include immigrants and people in the US on temporary work visas.

Conducting field studies with transgenic mosquitos in the US would send a strong signal about the safety and utility of the technology to other countries. But the debates over these field studies—fraught as they are by environmental, social, and political issues—look set to continue. O’Connor’s paper provides a useful starting point for understanding the critical arguments from all sides.